<template>
    <div class="todo-footer" v-show="total">
        <label>
          <input type="checkbox" :checked="isAll" @click="checkAll"/>
        </label>
        <span>
          <span>已完成{{todoCompleted}}</span> / 全部{{total}}
        </span>
        <button class="btn btn-danger" @click="clearAll">清除已完成任务</button>
      </div>
</template>

<script>
export default {
    name:'MyFooter',
    props:['todos'],
    computed:{
      total(){
        return this.todos.length
      },
      todoCompleted(){
        return this.todos.reduce((pre,current)=>{
          return pre+(current.done ? 1 : 0)
        },0)
      },
      isAll(){
        return this.total === this.todoCompleted && this.total > 0
      }
    },
    methods:{
      checkAll(e){
        // this.checkAllApp(e.target.checked)
        this.$emit('checkAllApp',e.target.checked)
      },
      clearAll(){
        // this.clearAllApp()
        this.$emit('clearAllApp')
      }
    }
}
</script>

<style scoped>
/*footer*/
  .todo-footer {
    height: 40px;
    line-height: 40px;
    padding-left: 6px;
    margin-top: 5px;
  }

  .todo-footer label {
    display: inline-block;
    margin-right: 20px;
    cursor: pointer;
  }

  .todo-footer label input {
    position: relative;
    top: -1px;
    vertical-align: middle;
    margin-right: 5px;
  }

  .todo-footer button {
    float: right;
    margin-top: 5px;
  }

</style>